Liquid fuel burner or injector



May 29, 1934. E. A. FRANKS LIQUID FUEL BURNER OR INJECTOR Filed June 21, 1953 Patented May 29, 1934 UNITED STATES- PATENT OFFICE Application June 21, 1933, Serial No. 616,951 In Great Britain September 22, 1931 8 Claims.

This invention relates to liquid fuel injectors for use in Diesel or semi-Diesel and other internal combustion engines or burners for use in boilers heated by liquid fuel.

In such injectors or burners, and especially injectors for small engines, difficulty has hitherto been experienced in the following respects:

1. In forming a nozzle orifice so small as to only deliver the correct amount of fuel and yet not to be choked by any foreign impurities such as grit, etc., in the fuel.

2. In preventing the fuel from blowing back or tailing off at the end of the fuel injection period, 1. e., the condition which occurs in certain types of burners or injectors due to a somewhat gradual lowering of the applied pressure this having for effect to cause the spray gradually to reduce and finally to form globules at the injector orifice.

3. In preventing the formation of carbon at the nozzle.

4. In keeping the injector or burner cool, and

5. In constructing an injector or burner in a simple manner and one easily taken apart and cleaned.

The main object of the present invention is to provide an improved injector or burner in which these defects are obviated or minimized.

The invention is illustrated in the accompanying drawing, in which Figure 1 is a vertical section on the line I-I Figure 3 with some parts shown in elevation, Figure 2 a vertical section on the line IIII Figure 3, and Figure 3 a local transverse section along the line III of Figure 2. I is a body shaped in a suitable manner at the end projecting towards the engine cylinder to form a diffusing nozzle 2. The body 1 is provided with connections 3, 4, 5, for fuel, air and water. The body contains two semi-circular cylindrical pieces 6 which are spaced apart to provide a groove or recess. In this groove there are located two plate like parts 8, 9, which are shaped as indicated at 7 to form a fuel supply passage: the two parts are shaped at their upper ends to form in conjunction with the parts 6, a nozzle 10, the two parts 8, 9 abutting at the nozzle when in their normal position. For the sake of clarity these parts 8 and 9 are shown in elevation in Figure 1. The part 8 is rigidly held between the two pieces 6 and the part 9 is slightly thinner than the part 8 (the relative thickness of the parts 8 and 9 being shown to an exaggerated extent in Figure 3) so that the part 9 is capable of being sprung away from the part 8 against the action of a spring ed lunger 11 which can be regulated by an adjusting screw 12. The part 9 is also shaped along its outer edge so as to provide the necessary clearance with respect to the inner wall of the body 1.

The cut away portion 7 forming the fuel supply passage is placed in communication with the fuel connection 3 by a chamber 13 formed conjointly by the pieces 6.

Between the nozzle end of the member 8, 9 and a cap 14 there is formed a chamber in which is located a valve 15 having a slight axial movement which is controlled by springs 16. The cap 14 is provided with a groove 17 which communicates with a groove 18 formed in the periphery of one of the pieces 6 and this latter groove is in turn in communication with the water connection 5. The pieces 6 and the members 8, 9 are so shaped at their upper ends as conjointly to form a groove 19 which communicates with a passage 20 formed in one of the pieces 6 and in communication with-the air connection 4.

In operation, the fuel delivered to the passage '7 cannot escape from the nozzle unless sufflcient pressure is exerted by the fuel to overcome the compression of the spring pressed plunger 11 and the fineness of the spray issuing from the nozzle depends upon the amount of pressure exerted by thespring.

It will also be seen that if compressed air is forced through the groove 19 and the time synchronized with that of the fuel supply an efficient atomization of the fuel will take place at the nozzle, the valve 15 being lifted from its seat by the air pressure against the action of the spring 16. This control of the degree of atomization of the fuel is effected by automatically controlling the pressure at the nozzle.

At the end of the injection period the spring pressed plunger 11 will operate on the part 9 and close the fuel nozzle-and, the air supply being cut off, the valve 15 will close or cover the air groove 19. At any predetermined time other than that of the fuel and air injection period the water injection can be brought into operation by pressure being exerted on a controlled water supply, thereby cooling the burner end and also removing carbon deposit.

It will further be seen that a stoppage at the nozzle through foreign matter in the fuel is rendered impossible or unlikely as the fuel pressure would open the orifice to allow of such obstruction being expelled.

The faces of the movable plate are not liable to distortion by grit or foreign matter being trapped as occurs when such matter gets on the face of the ordinary circular valve seat, and, moreover, the orifice can be made so narrowas compared with the circumferential length of the smallest circular seated valve that the kinetic energy of the issuing fuel is much greater, and therefore atomization more perfect.

What I claim is:-

1. In a liquid fuel burner or injector, a two-part housing, two plate-like parts located between the two parts of the two-part housing, the housing and the plate-like parts conjointly providing the fuel supply passage of the burner, one of the plate-like parts being clamped between the two parts of the housing to constitute a distance piece providing clearance forv the bodily passage opening and closing movement of the other plate-like part, spring means operating on the movable part externally of the passage and resiliently reacting against the bodily passage opening movement of the said part and means for adjusting the loading of the spring means.

2. In a burner or injector, a pair of plate-like 7 parts, a pair of housing members between which the plate-like parts are located, the housing and the plate-like parts conjointly providing the fuel supply passage of the burner, a casing for the housing members having a fuel supply conduit therein, the housing members clamping one plate-like part in position and permitting the other bodily passage opening and closing movement, and the passage being in communication with the supply conduit in the casing, a plunger bearing externally of the passage against the bodily movable plate like part, an adjustable member and a spring interposed between the adjustable member and the plunger to control the passage opening movement of the movable plate like part.

3. In a liquid fuel burner or injector, a casing having fuel, air, and water conduits and an outlet orifice, a two-part housing in the casing, two plate-like parts located between the two parts of the two-part housing, the housing and the plate-like parts conjointly providing the fuel supply passage of the burner, the passage being in communication with the fuel conduit, one of the plate-like parts being clamped between the two parts of the housing to constitute a distance piece providing clearance for the bodily passage opening and closing movement of the other platelike part, spring means for resiliently reacting against the bodily movement of the movable plate-like part, and a valve located in the casing and arranged automatically to be actuated by the pressure of the air and water supplies so as to place the conduit of one supply in communication with the orifice of the casing and at the same time to cut off the conduit of the other supply from the said orifice.

4. In a liquid fuel burner or injector, a casing having fuel, air, and water conduits and an outlet orifice, a two-part housing in the casing, two plate-like parts located between the two parts of the two-part housing, the housing and the platelike parts conjointly providing the fuel supply passage of the burner, the passage being in communication with the fuel conduit, one of the plate-like parts being clamped between the two parts of the housing to constitute a distance piece providing clearance for the bodily passage opening and closing movement of the other plate-like part, spring means for resiliently reacting against the bodily passage opening movement of the movable plate-like' part, means for adjusting the loading of the spring means, and a valve located in the casing and arranged automatically to be actuated by the pressure of the air and water suppliesso as to place the conduit of one supply in communication with the orifice of the casing and at the same time to out off the conduit of the other supply from the said orifice.

5. In a burner or injector, a casing having fuel, air, and water conduits and an outlet orifice, a pair of plate-like parts, a pair of housing members located in the casing and between which the plate-like parts are located, the housing and the plate-like parts conjointly providing the fuel supply passage of the burner, the passage being in communication with the fuel conduit, the housing members clamping one plate-like part in position and permitting the other bodily passage opening and closing movement, the passage being in communication with the supply conduit in the casing, a plunger bearing externally of the passage against the bodily movable plate-like part, an adjustable member, a spring interposed between the adjustable member and the plunger to control the passage opening movement of the movable plate-like part; and a valve located in the casing and arranged automatically to be actuated by the pressure of the air and water supplies so as to place the conduit of one supply in communication with the orifice of the casing and at the same time to cut off the conduit of the other supply from the said orifice.

6. In a liquid fuel burner or injector, a casing having fuel, air, and water conduits and an outlet orifice, a two-part housing in the casing, two plate-like parts located between the two parts of the two-part housing, the housing and the platelike parts conjointly providing the fuel supply passage of the burner, the passage being in communication with the fuel conduit, one of the plate-like parts being clamped between the two parts of the housing to constitute a distance piece providing clearance for the bodily passage opening and closing movement of the other platelike part, spring means for resiliently reacting against the bodily passage opening movement of the movable plate-like part, and a valve located in the casing and arranged automatically to be actuated by the pressure of the air and water supplies so as to place the conduit of one supply in communication with the orifice of the casing and at the same time to cut off the con-- duit of the other supply, the valve comprising a disc located concentrically with and in the outlet region of the fuel supply passage.

'7. In a liquid fuel burner or injector, a casing having fuel, air, and water conduits and an outlet orifice, a two-part housing in the casing, two plate-like parts located between the two parts of the two-part housing, the housing and the plate-like parts conjointly providing the fuel supply passage of the burner, the passage being in communication with the fuel conduit, one of the plate-like parts being clamped between the two parts of the housing to constitute a distance piece providing clearance for the bodily passage opening and closing movement of the other plate-like part, spring means for resiliently reacting against the bodily passage opening movement of the movable plate-like part, means for adjusting the loading of the spring means, and a valve located in the casing and arranged automatically to be actuated by the pressure of the air and water supplies so as to place the conduit of one supply -in communication with the orifice of the casing and at the same time to cut off the conduit of the other supply from the said orifice, the valve comprising a disc located concentrically with and in the outlet region of the fuel supply passage.

8. In a burner or injector, a casing having fuel, air, and water conduits and an outlet orifice,

a pair of plate-like parts, a pair of housing members located in the casing and between which the plate-like parts are located, the housing and the plate-like parts conjointly providing the fuel supply passage of the burner, the passage being in communication with the fuel conduit, the housing members clamping one plate-like part in position and permitting the other bodily passage opening and closing movement, the passage being in communication'with the supply conduit in the casing, a plunger bearing externally of the passage against the bodily movable platelike part, an adjustable member, a spring interposed between the adjustable member and the plunger to control the passage opening movement of the movable plate-like part, and a valve located in the casing and arranged automatically to be actuated by the pressure of the air and water supplies so as to place the conduit of one supply in communication with the orifice of the casing and at the same time to cut oil the conduit of the other supply from the said orifice, the valve comprising a disc located concentrically with and in the outlet region of the fuel supply passage.

. ERNEST ARTHUR FRANKS. 

